Using nested
reports
When designing a DataWindow object for a report, you can choose to
nest other reports (which are also DataWindow objects) within it. The
basic steps for using nested reports in an application are the same ones
you follow for the other report types. There are, however, some additional
topics concerning nested reports that you should know about.
To learn about designing nested reports, see Using Nested Reports in Users Guide.
Printing multiple updatable DataWindows on a
page
An advantage of composite reports is that you can print multiple
reports on a page. A limitation of composite reports is that they are not
updatable, so you cannot directly print several updatable DataWindows on
one page. However, there is an indirect way to do that, as follows.
You can use the GetChild method on named nested reports in a
composite report to get a reference to a nested report. After getting the
reference to the nested report, you can address the nested report during
execution like other DataWindows.
Using this technique, you can call the ShareData method to share
data between multiple updatable DataWindow controls and the nested reports
in your composite report. This allows you to print multiple updatable
DataWindows on a page through the composite report.
To print multiple DataWindows on a page using a composite
DataWindow:
-
Build a window or form that contains DataWindow controls with
the updatable DataWindow objects. -
Define a composite report that has reports corresponding to each
of the DataWindows in the window or form that you want to print. Be
sure to name each of the nested reports in the composite
report.Naming the nested report
To use GetChild on a nested report, the nested report must
have a name. To name a nested report in the DataWindow painter,
double-click it in the workspace and enter a name in the Name box on
the General property page. -
Add the composite report to the window or form (it can be
hidden). -
In your application, do the following:
-
Retrieve data into the updatable DataWindow controls.
-
Use GetChild to get a reference to the nested reports in the
composite report. -
Use ShareData to share data between the updatable DataWindow
objects and the nested reports. -
When appropriate, print the composite report.
-
The report contains the information from the updatable DataWindow
objects.
Re-retrieving data
Each time you retrieve data into the composite report, all
references (handles) to nested reports become invalid, and data sharing
with the nested reports is terminated. Therefore, be sure to call
GetChild and ShareData each time after retrieving data.
Creating and destroying nested reports during
execution
You can create and destroy nested reports in a DataWindow object
dynamically during execution using the same technique you use to create
and destroy other controls in a DataWindow object.
Creating nested reports
To create a nested report, use the CREATE keyword with the Modify
method. Supply the appropriate values for the nested report’s
properties.
Viewing syntax for creating a nested report
The easiest way to see the syntax for creating a nested report
dynamically is to export the syntax of an existing DataWindow object
that contains a nested report. The export file contains the syntax you
need.
For more information about exporting syntax in the Library
painter, see Users Guide.
When creating a nested report, you need to re-retrieve data to see
the report. In a composite report, you can either retrieve data for the
whole report or use GetChild to get a reference to the new nested report
and retrieve its data directly. For nested reports in other reports, you
need to retrieve data for the base report.
Destroying nested reports
To destroy a nested report, use the DESTROY keyword with the Modify
method. The nested report disappears immediately.
For more about creating and destroying controls in a DataWindow
object or report, see Dynamically
Changing DataWindow Objects.
For a list of properties of nested reports, see the section called “Properties for Report controls in DataWindow objects” in DataWindow Reference.